"What if you could essentially fake your death online - completely delete any trace of yourself from Facebook, Twitter, blogs, forums, Usenet, and anywhere else there might be some record of your existence. Such a concept is largely impossible today, especially given complications from services like Facebook combined with caches and mirrors of practically everything ever e-created. The European Commission wants to change that."

In this case I can answer : some guys have really screwed up on the internet around here, enough to attract the attention of legal powers.

Why can't existing slander laws work in the case you cite?

The power of government to force people against their will to delete data on the Internet can be used for evil. They come in with noble sounding goals, of course. "This is to protect you. We are here to help." - words of tyrants throughout history. Clever people word these sorts of laws in ways that can be exploited in unforeseen ways.

Governments like to rewrite history and silence criticism and what better framework is there when a government doesn't have authority to force people to delete publicly accessible data than with laws like this?